Why would Brainiac shrink a city like Kandor? An experiment. Apparently, Brainiac shrunk cities from several worlds for space travel, and was then going to re-inflate them when he found a suitable world. He would then reign over the cities. Sure it sounds good in theory, but I prefer my cities bite-sized – just like my candy bars.

Do you think Superman ever wants to give Kandor a good shake? Of course not. That would be…too much fun. Just imagine their tiny little screams.